LONDON, April 3 (Reuters) - AstraZeneca boosted its early-stage pipeline of experimental heart drugs on Wednesday by buying privately held U.S. biotechnology company AlphaCore Pharma, which is developing a new type of cholesterol medicine.

The deal shows AstraZeneca’s new Chief Executive Pascal Soriot taking on more scientific risks by betting on a new and still unproven approach to cardiovascular medicine.

Financial details of the acquisition by the British drugmaker’s MedImmune unit were not disclosed but the amount paid will have been modest since AstraZeneca was not obliged to disclose it as a material investment.

Last month it revealed it paid $240 million upfront to Moderna Therapeutics to access its know-how in manipulating RNA, or ribonucleic acid, which helps create proteins inside cells - another example of Soriot placing a bet on new science.

Soriot has stated that he plans to build up the company’s sparse drug pipeline by striking more deals with outside partners as he tries to restock its product portfolio following a wave of patent expiries.

Cardiovascular and metabolic disease - one of three core therapy areas for AstraZeneca, along with oncology and respiratory/inflammation - is a particular priority since the company has few experimental compounds for such conditions.

AlphaCore will help plug the gap, although it will not deliver any marketable products for many years. Its leading drug candidate ACP-501, a genetically engineered liver-derived enzyme called LCAT, only completed Phase I clinical tests last year.

Drugs need to go through three phases of lengthy tests before being approved for sale.

The hope is that ACP-501 will help in the management of cholesterol to reduce the risk of heart attacks and strokes. It could also play a role in a rare, hereditary disorder called familial LCAT deficiency in which the LCAT enzyme is absent.

MedImmune head Bahija Jallal said the end result could be new combination or standalone therapies for patients living with chronic and acute cardiovascular diseases.

SMART RISKS

In the past, AstraZeneca has been relatively cautious about exploring new drug approaches but Soriot, who joined from Roche last October, has signalled a change of direction.

He complained last month that AstraZeneca had lost some of its scientific confidence. “Smart risk taking is part of how you run an innovation business. There is no innovation without risk,” he said.

Soriot has embarked on a major restructuring of the group, which will cost $2.3 billion and involve shedding one in 10 jobs. At the end of the process, he aims to have a more focused drug research machine, better placed to tap into cutting-edge science.

It promises to be a long haul but AstraZeneca believes it can double the number of drugs in late-stage development by 2016, from just six today.

Industry analysts believe AstraZeneca could spend $20 billion on acquisitions and there has been speculation of a large deal, such as buying on Shire. Soriot, however, favours bolt-on deals and has previously said a major buy is possible but unlikely.

The acquisition of Ann Arbor, Michigan-based AlphaCore and the recent deal with Moderna may be more typical of his style.